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<body class='hmmessage'><div dir='ltr'><p style="margin: 0.0px 0.0px 14.0px 0.0px; font: 15.0px 'Helvetica Neue'; color: #333233">I have QGis1.8.0-Lisboa and the Raster Terrain Analysis Plugin on Mac/OS. When I want to build a raster layer of an aspect group with the Raster Calculator (e.g.: "aspect@1>=45 AND aspect@1<135" to do the East raster) that works. I have the good raster with a band 1 representing truly the East. Same concluding result with the 2 other exposures using AND (S & W). But for the North I do "aspect@1>=315 OR aspect@1<45" the resulting file doesn't have any band! nothing under band1 in Metadata (all is black for this layer on the screen). In alternative, I want to merge a raster with "aspect@1>=135" and a raster with "aspect@1<45" (Raster/ Miscellaneous/Merge) (GDAL tool) but it give me a layer with a band of only one of the 2 values groups ("aspect@1>=135" or "aspect@1<45")! Sorry for my levels of english and GIS.</p> </div></body>
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